Heat exchanger device



Jan. 20, 1953 RAsKlN HEAT EXCHANGER DEVICE Filed Aug. 19, 1949 FIG. I.

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IN V EN TOR. LEON ASK I N ATT oQN EY.

Patented Jan. 20, 1953 UNITED STATES PATENT OFFICE HEAT EXCHAN GER DEVICE Leon Raskin, Brooklyn, `N. Y.. Application August 19, 1949, Serial No. 111,131

2 Claims. 1

'I'he present invention relates generally to heat y exchangers and is concerned more particularly with an improved cold plate or evaporator plate for refrigerated cabinets such as are commonly employed in soda fountains and cabinets for the storage of ice cream, beverages, frozen foods and the like. The invention is also suitable as panel heaters, base board heaters, radiant heaters and for heating buildings as Well as for heating uids in industrial processes.

It is a general object of the invention to provide a heat exchanger or evaporator plate which is constructed and arranged in such a manner as to be characterized by a reduced pressure drop between the inlet and the outlet end thereof, thereby resulting in enhanced heat exchange and enhanced efficiency.

A particular object of the invention is the provision of an evaporator plate having an expansion chamber comprising a sinuous refrigerant passageway wherein certain of the bends or convolutions thereof are subdivided by means of parallel ducts in a novel manner insuring reduced friction to the iiow of fiuids, minimum expenditure of energy in conveying the heat exchange medium from one group of ducts to the next and a complete ooding of the refrigerant passageway.

Another obj ect of the invention is the provision of a heat exchange evaporator plate of the character indicated which may be readily and inexpensively fabricated in a variety of shapes such as a fiat plate, a U-shaped structure, an L- shaped structure, a boxlike structure, a cylindrical structure or the like.

The foregoing objects as well as additional objects and advantages of the invention will be readily apparent in the course of the following detailed description taken in connection with the accompanying drawing which illustrates preferred embodiments of the invention, and wherein:

Fig. 1 is a front elevational view of an evaporator plate embodying the features of the invention;

Fig. 2 is a front elevational view of a modied form of evaporator plate;

Fig. 3 is a fragmentary sectional view taken along line 3-3 of Fig. 1; and

Fig. 4 is a perspective view of an additional modification of the invention.

Referring first to Figs. 1 and 3 the evaporator plate, which is generally designated by reference numeral I0, comprises a pair of superposed metal sheets II and I2 which are preferably, but not necessarily, rectangular in shape. One or both of said sheets is embossed. stamped or processed in any other suitable manner to define a continuous sinuous convolution or corrugation I3. In the embodiments of the invention illustrated in the drawings, sheet I I is shown as being formed with the sinuous corrugation I3 while sheet I2 is iiat. The contiguous portions of sheets I I and l2 between corrugation I3 and along the edges of the sheet are secured together in any suitable manner as by seam welding or spot welding (not shown) so that the sinuous corrugation I3 defines a leakproof continuous passageway for the refrigerant. Said passageway serves as an expansion chamber for the refrigerant passing through the evaporator plate I0 and the particular advantages and special characteristics of the passageway which serve combinedly to achieve the objects of theinvention will be described more fully hereinafter.

As may be seen in Fig. 1, the refrigerating medium such as sulphur dioxide, isobutane, methyl chloride, ammonia, Freon, etc. enters refrigerant passageway I3 through inlet duct I4 whereupon it will vbe divided into two streams passing through the parallel ducts I5. It will be noted that the area of the refrigerant passageway I3 between inlet duct I4 and the parallel ducts I5 is reinforced by means of a spot welded, preferably circular indentation I6 in order to prevent distortion and expansion of the metal due to excessive internal pressure. As may be seen in the drawings and as will appear hereinafter, the remaining bights or bends of the refrigerant passageway are also provided with indentations I6 for a similar purpose.

The refrigerating medium passes through the initial parallel ducts I5 to the first bight I'I, thence around the identations I6 and into a successive pair of parallel ducts I8, thence through the bight I9 and into a third pair of parallel ducts 20, thence through the bight 2 I and through a fourth pair of parallel ducts 22 and nally through the outlet duct 23. It will be noted that the bights or bends connecting the parallel ducts are arranged and constructed in such a manner as to offer a minimum resistance to the ow of refrigerant therethrough. Consequently there will be a minimum waste of energy in conveying the refrigerant from one group of parallel ducts to the next. At the same time the provision of the sinuous passageway assures a reduction of friction as well as complete flooding of a, maximum area of the evaporator plate. Sheets II and I2 are preferably seam welded between their parallel ducts and spot welded at their bight portions to dei-ine the spaced parallel indentations I6.

Fig. 2 illustrates a modified form of evaporator plate having a somewhat different design and increased capacity over the modification initially described. In this connection it will be understood that the number of parallel ducts in each convolution or the number of convolutions may be varied as desired .and consistent with the exigencies of particular situations fand :conditions The embodiment of Fig. 2 illustrates an evaporator plate 25 provided with an inlet opening 2,6 through which the refrigerating medium is introduced directly into the bight 21 and lthence into the first group of three parallel ducts 28. The refrigerant then passes into the bight2'9 ani'then into the second group of threejparallel ducts 32). 'Ihe remaining portion of the evaporator plate is iiooded in a similar manner and the Arefrigerant finally passes through the outlet duct 3l from which -it may be Vconducted'to Lv'additional #plates ofthe refrigeratingsystem. A

It W-ill Vbe furthernote'd that -the bightl'portions of evaporator plateZ ypreferably Vhave acrosssectional Larea substantially the same orv greater -thanthe Vaggregatearea df-the threeducts228 or 3E) communicating:withvsaidbightportion '-The in'dentationsiBZforrnedin thebight portions serve similarlyy totheindentations I 6 -of the! initial-em- 'bodiment to prevent vdistortion or expansion .of the bight portionsof 'fthe refrigerant passageway due to lexce'ssive -f internal :.pressure. l Said 1 indenitations maybe. formedby-lspotzwelding-.on by form pressing-or,someothermetho'd.

Asihas been previ'cmsly.point-ed` out,the;evapo rator velements Lof the ipresent'` invention-maybe fabricated VJin alargevarietyfotzshapesfsand; forms diieringffrom the-atplateemb'o dimentstofFigs. 1 to3. 'Fig.4 illustratesi-a 'boxJ-type evaporator element 35 constructed according tothe principles 'of Vthe present invention. "The v:upstanding walls .of "the .element E35 .mavabe:providedzvvithYv a Asinuous ,passagewayl 3 6 in 'thexnannerr described for `the V.initial :embodiments vand ..may Athen be 4shaped to'theidesired configuration. -Thebights or :bends of `Tthe refrigerantipassagewayfSSfare also" reinforced by means :of indentations 3l. which may fbe s'pct `welded to prevent expansion :and distortion of" thecsheets iforming 'the element35. An :inlet vopening "3 8 iand .fan `:outlet izopeningls rare.; provided ifor"V the refrigerating medium.

Since certain modificati-ons may be made in the device of the invention without departing from the scope thereof, it is intended that all matter contained in the foregoing specication and shown in the accompanying drawing be interpreted merely as illustrative and not in a limiting sense.

What is claimed is:

1. vvInan evaporator plate forrefrigerating sysytems, a pair of superimpsed metal ,ps heets, at least one of said sheets being provided with a 4continuous sinuous depression extending through the area of said sheet, said depression having parallelllegportions with intervening bight portions. saidleg portions being subdivided into a plurality o'f spaced parallel ducts terminating in said bight zpo'rticns, seach of :said bight portions having a cross-sectional area not less than the aggregate area 'of the ducts in each of said leg portions. said sheets having a longitudnalcontinuous vdepression -intermediate Asaid parallel vduc-ts, said b ight p'ortionsbeing leenzh"provided with a plurality -of substantially circular 'indentations at spaced'pointsbetweenthe ducts 4to form a series of :intercommunicating passageways in communication with-the severalducts each of thesaid indentations having a `diameter approximately equal-to thewidth of'each ofsthegducts.

V2. YIn an evaporator-plateas'provided for in claim l, wherein the substantially circular'in- 'dentations are spaced-aparta distance substantially equal to the width of each gof 'the ducts. and said indentations'are each in Aalignment with spaces between the ducts.

LEON'RASKTN.

.REFERENCES a .CITED The following references :are pf'record in f the file of this patent:

UNITED STATES .PATENTS Nlunber .'Name VDate 2,028,457 :Karmazin J an. 21, '.1936 2,143,976 Crosley'etaal Jan. 17,1939

2,244,475 Raskin June, 1941 2,481,511 Hubbell v.Sept-, 13, 1949 2,481,512 Hubbell Sept. 13,1949 1481.556 Wohl Sept.'13,f1949 2;4'96g558 vPhilipp ?"Feb.l"7, 1950` 

